Successfully perceiving and recognizing the actions of others is of utmost importance for the survival of many species. For humans, action perception is considered to support important higher order social skills, such as communication, intention understanding and empathy, some of which may be uniquely human. Over the last two decades, neurophysiological and neuroimaging studies in primates have identified a network of brain regions in occipito-temporal, parietal and premotor cortex that are associated with perception of actions, also known as the Action Observation Network. Despite growing body of literature, the functional properties and connectivity patterns of this network remain largely unknown.

The goal of this dissertation is to address these general questions about functional properties and connectivity patterns with a specific focus on whether this system shows specificity for biological agents. To this end, we collaborated with a robotics lab, and manipulated the humanlikeness of agents that perform recognizable actions by varying visual appearance and movement kinematics. We then used a range of measurement modalities including cortical EEG oscillations, event-related brain potentials (ERPs), and fMRI together with a range of analytical techniques including pattern classification, representational similarity analysis (RSA), and dynamical causal modeling (DCM) to study the functional properties, temporal dynamics, and connectivity patterns of the Action Observation Network.

While our findings shed light on whether the human brain shows specificity for biological agents, the interdisciplinary work with robotics also allowed us to address questions regarding human factors in artificial agent design in social robotics and human-robot interaction such as uncanny valley, which is concerned with what kind of robots we should design so that humans can easily accept them as social partners.

Please join us and find out more about some of Burcu’s exciting and interdisciplinary work in the lab!

Tool use is a hallmark of the human species and an essential aspect of daily life. Tools serve to functionally extend the body, allowing the user to overcome physical limitations and interact with the environment in previously impossible ways. Tool-body interactions lead to significant modulation in the user’s representations of body size, a phenomenon known as tool embodiment. In the present dissertation, I used psychophysics and event-related brain potentials to investigate several aspects of tool embodiment that are otherwise poorly understood.

First, we investigated the sensory boundary conditions of tool embodiment, specifically the role of visual feedback during tool use. In several studies, we demonstrate that visual feedback of tool use is a critical driver of tool embodiment. In one such study, we find that participants can embody a visual illusion of tool use, suggesting that visual feedback may be sufficient for tool-induced plasticity.

Second, we investigated the level of representation modulated by tool use. Is embodiment confined to sensorimotor body representations, as several researchers have claimed, or can it extend to levels of self-representation (often called the body image)? Utilizing well-established psychophysical tasks, we found that using a tool modulated the body image in a similar manner as sensorimotor representations. This finding suggesting that similar embodiment mechanisms are involved at multiple levels of body representation.

Third, we used event-related brain potentials to investigate the electrophysiological correlates of tool embodiment. Several studies with tool-trained macaques have implicated multisensory stages of somatosensory processing in embodiment. Whether the same is true for humans is unknown. Consistent with what is found in macaques, we found that using a tool modulates an ERP component (the P100) thought to index the multisensory representation of the body.

The work presented in this dissertation advances our understanding of tool embodiment, both at the behavioral and neural level, and opens up novel avenues of research.

Please join us and find out more about some of Luke’s exciting research in the lab over the past few years!

Our lab is proud to announce that Burcu Aysen Urgen, a graduate student in Cognitive Science, was one of the winners of this year’s Interdisciplinary Scholar Awards organized by the UCSD Graduate Student Association (GSA) in coordination with the Office of Graduate Studies.

Burcu was our department’s nominee this year. A committee composed of a diverse group of graduate students and faculty selected three awardees, who each received a $500 honorarium and a fancy trophy (see photos below). The students presented their award-winning research at the 2013 Interdisciplinary Research Awards Ceremony on April 4, 2013. A group of lab members and other graduate students from the department attended the event, which featured an address by Kim Barrett (dean of graduate studies), presentations by the awardees, as well as food and drinks. Burcu’s talk was entitled “Spatio-temporal neuroimaging of visual processing of body movements in humans”; an abstract of her talk is included below. Congratulations Burcu!

Recognizing the actions and body movements of others is of utmost importance for the survival of many species. For humans, action recognition is considered to support important higher order social skills, such as communication, intention understanding and empathy, some of which may be uniquely human. Over the last decade, neurophysiological and neuroimaging studies in primates have identified a network of brain regions that are associated with recognition of body movements. The main goal of this interdisciplinary project is to investigate whether this neural system shows specificity for conspecifics, particularly for humans. This general question is addressed by using state-of-the-art robots, which were provided by a robotics lab, non-invasive brain imaging methods with excellent temporal and spatial resolution (EEG and fMRI, respectively), and advanced data analysis techniques from computer science.

Hello! This is Cindy, and I am a research assistant at the Saygin Lab of Cognitive Neuroscience and Neuropsychology. I’ve been doing this for a few quarters now, and it’s been a great experience. You should join me!

Being a research assistant for the Saygin Lab really solidified why I became a cognitive science major. I switched into it not really knowing what my major was about, but through the weekly lab meetings and conversing with others, I came to realize how lucky I was to have stumbled upon UCSD’s diamond in the rough.

I knew about the work that our lab does beforehand was because I am a chronic frequenter of geek websites, such as Cracked.com. Although perhaps not the most established forum, it often brings up sci-fi related research, such as was being done in the lab. Robots are a common topic, and the phenomenon of the Uncanny Valley inevitably came up. Imagine how surprised I was when I was reading up on the research opportunities at the CogSci department at UCSD, and found that that research had been accomplished by one of the professors! I sent in an application and was ecstatic when I was accepted.

I didn’t know what I was getting myself into, since my pre-med friends were always going on about how they created buffer solutions in chem research or cut up rats in bio research. Turns out that the experiments I was running for my grad student researcher was most like psychology research. Luke (the grad student) had us running a two session, two hour each experiment, which was not the most interesting thing I’ve ever done. When I talked to him about what I was collecting data for though, that was what was the exciting part. The overarching theme was something about embodied cognition and how we projected ourselves in space. For example, how do amputees see and feel about their prosthetics? It’s not technically a part of them, yet it should ideally function just as well or even better than what the respective limb did. He went on to do some research concerning a large plastic hand, similar to Edward Scissorhands. I did some external research and thought that this particular invention, a prosthetic arm that biomimics an octopus arm would yield interesting results pitting conventional arms vs. functionality.

How would these affect the self-perception of a human?

Lab members attend mini symposiums and conferences about where advances in cognitive science could lead to (in regards to technology). One that I was able to attend concerned the future of brain-computer interfaces or BCIs. Most of the technical engineering talk was lost on me, but the main thing I came away with was that pretty soon, we will be able to manipulate objects with our “minds.” This lead me to do some other outside research, and I found this prototype fashion accessory being demonstrated in conventions around the world: Necomimi Cat Ears. Its claim to fame is that it can change shapes when the wearer is focused or relaxed. This seems like an extraordinarily trivial application of this technology, but the concept is the same as more serious uses of BCIs. It is using EEG waves produced by the brain to control objects that aren’t necessarily part of a body.

The coolest thing about researching in this lab while being a CogSci major was probably seeing how this current research was being taught in our classes. The fMRI book we discuss in meetings have direct repercussions on what I’m learning in my neuroscience class, and knowing that there’s still much debate going on whether cognition is distributed or specialized puts a whole different spin on my distributed cognition class. It’s also opened up a lot of doors. This summer, I advised a couple high school students getting their first taste of research and during the school year (we will have another blog post about that soon), I will be in the process of completing the Cognitive Science Honors Program.

I hope this has convinced you to do research as an undergrad! Use your four years wisely.